Ecology: Population and Communities Flashcards
Abiotic?
Physical environment features.
Biotic?
Living features
Levels of ecology?
Individual, Populations in ecology, community, ecosystem.
What’s population ecology?
Many individuals of same species
What’s a community?
Multiple members of different species.
Autocology?
Study of individuals in their environment.
Behavioral ecology?
How it’s body allows it to function in habitat so adaptation.
Population?
Group of individuals of a species that occupies an area.
3 types of species distribution?
Random, regular,clumped
Meta population?
Set of connected populations.
What are the measures of samples?
Per unit area
Per unit volume
Biomass - per unit area
Types of population density sampling?
Plot samples: Quadrats or transect.
Plotless samples: Mark/recapture or nearest neighbour analysis.
What do life tables measure?
Birth, Death, Population dynamics.
What’s a cohort?
Group of individuals that were born at same time
What are the types of life table?
Cohort life table - Alive organisms at specific times and number of offspring they produce at different time intervals.
Statistic life table - Based on age distribution of population.
What can life tables be used to draw?
Survivorship curves.
Types of population growth?
Exponential - growth rate of population accelerates
Logistic - Rate accelerates to point of maximum growth and then slows down.
What’s the R rate?
Steep bit of curve is the maximum growth curve.
What’s the K rate?
Carrying capacity is max population size.
Population regulation?
Density - Independent factors
Density dependant factors - occur when carrying capacity is reached.
Difference between K and R adapted species?
R adapted - e.g Insects, rodents, parasites - short life/rapid growth/early maturity/many small offspring.
K adapted - e.g wolves, elephants, whales - long life/slower growth/late maturity/Fewer large offspring.
Community?
All species that live within a given area/habitat.
All types of interspecies relationships?
Neutral - Two species don’t interact
Mutualism - Both participants benefits
Commensalism - One participant benefits but other unaffected.
Amenalism - One participant is harmed but other is unaffected.
Predator-Prey or parasitic-host - one participant harmed, other benefits.
Competition - Both participants lose energy.
Types of change (succession)?
Primary - Starts from baron ground
Secondary - Disturbed area where organisms survived recent disturbance.
What are transitional communities?
Members of pioneer communities when they gradually change the habitat.
What’s a Climax community?
Stable, self perpetuated array of species in equilibrium with one another nd their habitats.
What’s the basic progression of Xerach succession on bare rock?
Bare rock > Lichen moss stage > Annual herb stage > Perennial herb stage > Scrub stage > Forests.
What’s a hydrosere?
A succession which starts with water.
What is intraspecific and interspecific competition?
Intraspecific - Within species
Interspecific - Between species
What’s a Niche?
Functional role of a species in a community.
What’s a fundamental niche?
The broadest possible niche a species can occupy.
Wat’s a realised niche?
The part of the fundamental niche that a species actually occupies after competition.
True or False? Can two species have the same niche?
Niches can overlap but no two species in a habitat have the same niche. One has to perform the niche better.
What’s a co-evolutionary arms race?
When two or more species coevolve. (Evolve to out compete or survive each other).
What are mutualisms?
Ranges from non-specific mutually beneficial associations to total dependency of two species on each other.
What’s a keystone species?
- A species which influences the entire community so it’s removal will cause the ecosystem to collapse.
- Influence both species richness of communities/flow of energy, and materials through ecosystems.
What’s an ecosystem?
All species that live within a given area together with all abiotic features of their environment.
